refactor: adjust chart render function

bar_chart.go

@@ -26,11 +26,7 @@ import (
 	"github.com/wcharczuk/go-chart/v2"
 )
 
-func BarChartRender(opt ChartOption) (*Draw, error) {
-	result, err := chartBasicRender(&opt)
-	if err != nil {
-		return nil, err
-	}
+func barChartRender(opt ChartOption, result *basicRenderResult) (*Draw, error) {
 	d := result.d
 
 	bd, err := NewDraw(DrawOption{

chart.go

@@ -30,6 +30,12 @@ import (
 	"github.com/wcharczuk/go-chart/v2/drawing"
 )
 
+const (
+	ChartTypeLine = "line"
+	ChartTypeBar  = "bar"
+	ChartTypePie  = "pie"
+)
+
 type SeriesData struct {
 	Value float64
 	Style chart.Style
@@ -158,6 +164,42 @@ type basicRenderResult struct {
 	yRange       *Range
 	d            *Draw
 	titleBox     chart.Box
+	seriesOffset int
+}
+
+func ChartRender(opt ChartOption) (*Draw, error) {
+	result, err := chartBasicRender(&opt)
+	if err != nil {
+		return nil, err
+	}
+	lineSeries := make([]Series, 0)
+	barSeries := make([]Series, 0)
+	for _, item := range opt.SeriesList {
+		switch item.Type {
+		case ChartTypeBar:
+			barSeries = append(barSeries, item)
+		default:
+			lineSeries = append(lineSeries, item)
+		}
+	}
+	if len(barSeries) != 0 {
+		o := opt
+		o.SeriesList = barSeries
+		_, err = barChartRender(o, result)
+		if err != nil {
+			return nil, err
+		}
+	}
+	if len(lineSeries) != 0 {
+		o := opt
+		o.SeriesList = lineSeries
+		result.seriesOffset = len(barSeries)
+		_, err = lineChartRender(o, result)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return result.d, nil
 }
 
 func chartBasicRender(opt *ChartOption) (*basicRenderResult, error) {

line_chart.go

@@ -27,11 +27,7 @@ import (
 	"github.com/wcharczuk/go-chart/v2/drawing"
 )
 
-func LineChartRender(opt ChartOption) (*Draw, error) {
-	result, err := chartBasicRender(&opt)
-	if err != nil {
-		return nil, err
-	}
+func lineChartRender(opt ChartOption, result *basicRenderResult) (*Draw, error) {
 
 	d := result.d
 	theme := NewTheme(opt.Theme)
@@ -55,7 +51,7 @@ func LineChartRender(opt ChartOption) (*Draw, error) {
 				Y: y,
 				X: xRange.getWidth(float64(j)),
 			})
-			seriesColor := theme.GetSeriesColor(i)
+			seriesColor := theme.GetSeriesColor(i + result.seriesOffset)
 			dotFillColor := drawing.ColorWhite
 			if theme.IsDark() {
 				dotFillColor = seriesColor